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The chubbyhead barb, Enteromius anoplus, as currently described, is the most widely distributed freshwater fish in South Africa. The species occurs in almost all the major river systems across the country, with the exception of the small coastal drainages on the south coast. The use of a comprehensive data set of mitochondrial (mtDNA) cytochrome b (cyt b) sequences uncovered the presence of four distinct lineages or operational taxonomic units (OTUs) within E. anoplus: (a) the Gouritz lineage endemic to the Gouritz River system, (b) the Olifants lineage endemic to the Olifants‐Doring River system, (c) the Orange lineage endemic to the Orange River system and (d) the Eastern Cape lineage which is distributed across six river systems from the Great Fish to the Buffalo rivers in the Eastern Cape Province of South Africa. The present study provides a new diagnosis for E. anoplus s.s. (the Gouritz lineage), revalidates Enteromius cernuus (the Olifants lineage) and Enteromius oraniensis (the Orange lineage) as distinct species. The study also provides a description for a new species, Enteromius mandelai sp. nov (the Eastern Cape lineage). E. cernuus and E. mandelai differ from both E. anoplus and E. oraniensis by having a complete lateral line (vs. an incomplete lateral line in the latter species). E. cernuus further differs from the other three species by having long maxillary barbels which reach or exceed the vertical through the middle of the eye and the lowest number of circumpendicular scales (10–12 vs. 12–16 for the other three species). E. oraniensis is distinctive from the other three species by having inconspicuous barbels. These findings add to the growing body of literature that shows that the freshwater fishes of the Cape Fold and adjacent freshwater ecoregions have narrow geographic ranges. This has ramifications for conservation planning and management, as well as the understanding of the evolutionary history of the stream fishes in these global endemic hotspots. [ABSTRACT FROM AUTHOR]

East African and south African churchills (Petrocephalus, Mormyridae) were synonymised in 1959 to become members of a single species of subcontinental, southern African distribution, Petrocephalus catostoma (Günther, 1866). By comparison with the type material for P. catostoma from the Ruvuma River and P. stuhlmanni from the Ruvu River, both of East African origin, we confirm the South African form of churchill to represent a new species, P. wesselsi, ranging from the northern Limpopo and Incomati systems south to the Pongola River (Natal) as its southern limit. We also compared churchills from the Sabie River (25° S, South Africa, Incomati system) with churchills from the Upper Zambezi River (17° S, Namibia), using electric organ discharges (EODs) and morphology. The duration of an EOD pulse of the South African form (N = 39; 943.2±S.E. 18.82 µs) is, on average, more than twice that of the Upper Zambezi form (N = 37; 436.6±15.1 µs), and the amplitude of the second head-positive phase (P2 phase relative to P1 = 1) significantly weaker (0.133 ± 0.0005 vs. 0.472 ± 0.002 for Upper Zambezi males, 0.363 ± 0.03 for Upper Zambezi females). In contrast to the Upper Zambezi form, the EOD of the South African form exhibits no difference between the sexes. Fish from the two origins differ significantly in 11 out of 14 anatomical characters studied, confirming molecular genetic differentiation on the species level. [ABSTRACT FROM AUTHOR]

Sandelia bainsii is an endangered freshwater fish species which onlyoccurs in short sections of several Eastern Cape river systems in South Africa. The spawning behaviour of S. bainsii is described for thefirst time. Female S. bainsii remained a light grey colour. Males exhibited distinctive nuptial coloration consisting of an intense blackwith a white bar on their caudal fin and white windows on the posterior areas of their dorsal and anal fins. There was a darkened post orbital contact organ of ctenoid scales on the reproductively active males. The spawning behaviour was recorded on a video recorder and analyzed during frame by frame replay. Sandelia bainsii are uniparental substrate breeders. The male prepared a spawning area by clearing the substrate with rapid body movements (sweeps). There were a number of preliminary courtship movements, several trial embraces by the male before the actual final embrace. The male underwent a U bend around the female, anchored himself with the contact organ, squeezed the abdominal area of the female with a quick head movement. Courtship and spawning all took place near the substratum. Twenty one separate mating bouts were filmed and analyzed. The duration varied from 1.44 to 5.11seconds with an average embrace of 3.39 seconds. During the mating clench the female was not normally turned over, as in some anabantoids, but remained upright. The male then guarded the spawning area. Eggswere light yellow, adhesive, demersal and 1.28 mm in diameter with 0.61 mm oil globules. The breeding behaviour of S. bainsii has some similarities with both breeding behaviourial groups, the bubble nestersand the free spawners, within the other African anabantid genus, Ctenopoma. Sandelia bainsii have acquired some temperate specializationswith regard to their reproductive style. Free spawning and the release of buoyant eggs is the plesiomorphic anabantid reproductive style.The demersal eggs and male substratum nest sites of S. bainsii are considere [ABSTRACT FROM AUTHOR]